Osteosynthesis plates for stabilization of bone fractures typically are applied with bone screws. Traditionally, bone screws compress a plate onto the bone surface to provide stable fixation. More recently, locking plates have been introduced, which typically have threaded receiving holes for positive, angle-stable engagement with the threaded head portion of a locking screw. These locking plates may provide more stable fixation in the ends of weak, osteoporotic bone compared to traditional, non-locking plates.
Clinically, plate osteosynthesis constructs face two principal challenges. First, an osteosynthesis construct may alter the load distribution in bone, which may either cause bone resorption in cases exhibiting load shielding, or bone fracture due to implant-induced stress risers. Second, the high stiffness of a plate osteosynthesis construct may suppress relative displacement between bone fragments, whereby this interfragmentary motion is important to promote the natural cascade of fracture healing by callus formation. Therefore, overly stiff locking plate constructs may delay or prevent fracture healing by callus formation.